1. Technical Field
This invention relates to key cutting machines capable of duplicating a master key by appropriately cutting a key blank and forming a key for use in a particular lock by utilizing devices controlling the spacing of the cuts in a key blank and the depth of the cuts in accordance with a lock and key manufacturer's code.
2. Description of Prior Art
Prior machines of this type are illustrated and described in U.S. Pat. Nos. 1,750,218 to M. Falk, 1,889,461 to H. Hansen and 1,948,260 to F.E. Fowler.
The Falk patent in its preferred embodiment utilizes two discs 34 and 35, one of these controlling transverse movement of the blank with respect to the cutter of the machine and the other disc controlling movement toward and away from the cutter wheel. A modification shown in FIG. 6 of the patent utilizes a single disc having a cam applied to one side thereof.
The Hansen patent utilizes an elongated bar which is slideable transversely of the machine, one end of the bar having a plurality of notches arranged on an angular plane and a series of apertures are formed in longitudinally spaced relation in the other end of the bar. The position of a key blank to be cut being controlled by means on the machine engaging the notches and the apertures in the elongated bar.
The Fowler patent utilizes two so called plates, one of which has a plurality of notches arranged in an angular plane along one edge and controls the depth of the cut to be made in a key blank and a spacing key having a plurality of notches spaced longitudinally therein controls the spacing of the cuts.
The present invention discloses a key cutting machine incorporating the usual rotary cutter and means movable toward and away and transversely of the rotary cutter in which one or more keys or key blanks can be positioned. The principle novelty in the present invention is the provision of a device incorporating removable and replaceable discs, each of which has a plurality of circumferentially spaced different depth cut-outs formed in one side thereof and means registrable with the cut-outs controlling the position of the key blank being cut with respect to the spacing of the cuts being formed in the key blank and the depth of the cuts.